diff --git a/server/commands/documentImporter.js b/server/commands/documentImporter.js
index efa615c48..4410914f7 100644
--- a/server/commands/documentImporter.js
+++ b/server/commands/documentImporter.js
@@ -5,6 +5,7 @@ import mammoth from "mammoth";
 import TurndownService from "turndown";
 import uuid from "uuid";
 import parseTitle from "../../shared/utils/parseTitle";
+import { InvalidRequestError } from "../errors";
 import { Attachment, Event, User } from "../models";
 import dataURItoBuffer from "../utils/dataURItoBuffer";
 import parseImages from "../utils/parseImages";
@@ -66,6 +67,9 @@ export default async function documentImporter({
   ip: string,
 }): Promise<{ text: string, title: string }> {
   const fileInfo = importMapping.filter((item) => item.type === file.type)[0];
+  if (!fileInfo) {
+    throw new InvalidRequestError(`File type ${file.type} not supported`);
+  }
   let title = file.name.replace(/\.[^/.]+$/, "");
   let text = await fileInfo.getMarkdown(file);
 
diff --git a/server/commands/documentImporter.test.js b/server/commands/documentImporter.test.js
index 2cac52725..66714eeea 100644
--- a/server/commands/documentImporter.test.js
+++ b/server/commands/documentImporter.test.js
@@ -74,4 +74,27 @@ describe("documentImporter", () => {
     expect(response.text).toContain("This is a test paragraph");
     expect(response.title).toEqual("Heading 1");
   });
+
+  it("should error with unknown file type", async () => {
+    const user = await buildUser();
+    const name = "markdown.md";
+    const file = new File({
+      name,
+      type: "executable/zip",
+      path: path.resolve(__dirname, "..", "test", "fixtures", name),
+    });
+
+    let error;
+    try {
+      await documentImporter({
+        user,
+        file,
+        ip,
+      });
+    } catch (err) {
+      error = err.message;
+    }
+
+    expect(error).toEqual("File type executable/zip not supported");
+  });
 });